Mattress with capacitive immersion control

ABSTRACT

A mattress and a capacitive immersion system for adjusting the support that the mattress provides to a user are disclosed. In one embodiment, a mattress includes one or more air cells and a capacitive immersion system. The system relates generated capacitance between conductors mounted to an air cell to a pressure inside the air cells on which the conductors are mounted. More specifically, the measured capacitance may be related to a distance between the conductors. This distance may then be related to pressure with the air cells. The air cell may be inflated or deflated as required or desired to maintain a suitable minimum distance or distance that a user finds to be subjectively comfortable.

PRIORITY CLAIM

This application claims the benefits of previously filed U.S. Provisional Patent Application entitled “CAPACITIVE IMMERSION SYSTEM FOR MATTRESS,” assigned U.S. Ser. No. 61/551,608, filed Oct. 26, 2011, and of previously filed U.S. Provisional Patent Application entitled “CAPACITIVE IMMERSION SYSTEM FOR MATTRESS,” assigned U.S. Ser. No. 61/674,523, filed Jul. 23, 2012, and both of which are incorporated herein by reference for all purposes.

FIELD OF THE SUBJECT MATTER

The presently disclosed subject matter relates generally to mattresses, and more specifically to systems for adjusting the support provided to users of mattresses, especially for the patient-care environment.

BACKGROUND OF THE SUBJECT MATTER

The design, construction, and use of mattresses and bed frames has been known and practiced for many years. In particular, mattresses and bed frames have been developed with various features for specific uses and in specific fields, such as in health care-related fields. For example, many known beds for hospitals and nursing homes include mattresses and bed frames with various features for adjusting the beds and for contributing to the safety of the patients utilizing the beds.

Examples of mattresses with various adjustable features are disclosed in, for example, U.S. Pat. No. 4,827,763 to Bourland et al. (disclosing a pressure mapping system with capacitive measuring pad), U.S. Pat. No. 4,873,737 to Savenije (disclosing a fluid filled mattress with height measuring and control devices), U.S. Pat. No. 5,010,772 to Bourland et al. (disclosing a pressure mapping system with capacitive measuring pad), U.S. Pat. No. 5,410,297 to Joseph et al. (disclosing a capacitive patient presence monitor), U.S. Pat. No. 5,449,002 to Goldman (disclosing a capacitive biofeedback sensor with resilient polyurethane dielectric for rehabilitation), U.S. Pat. No. 5,775,332 to Goldman (disclosing a capacitive biofeedback sensor with resilient polyurethane dielectric for rehabilitation), U.S. Pat. No. 6,009,580 to Caminade et al. (disclosing a method and apparatus for supporting an element to be supported, in particular the body of a patient, making it possible to support said element at a predetermined float line), U.S. Pat. No. 6,033,370 to Reinbold et al. (disclosing a capacitative sensor), U.S. Pat. No. 6,034,526 to Montant et al. (disclosing apparatus for controlling the inflation pressure of a mattress in response to deformation of the mattress using impedance measurement), U.S. Pat. No. 6,560,804 to Wise et al. (disclosing a system and methods for mattress control in relation to patient distance), U.S. Pat. No. 7,007,327 to Ogawa et al. (disclosing an adjustable bed), U.S. Pat. No. 7,107,642 to Wong et al. (disclosing an adjustable mattress and pillow system), U.S. Pat. No. 7,426,872 to Dittmar et al. (disclosing a sensor, device and method for measuring the pressure of an interface between two bodies), U.S. Pat. No. 7,469,572 to Bartlett (disclosing measurement of moisture vapor transfer rate), U.S. Pat. No. 7,641,618 to Noda et al. (disclosing a capacitance-type pressure sensor and heart beat/respiration measuring device using the same), U.S. Pat. No. 7,779,956 to Breed et al. (disclosing vehicular seats with weight sensing capability), U.S. Pat. No. 7,815,219 to Breed et al. (disclosing weight measuring systems and methods for vehicles), U.S. Pat. No. 7,916,036 to Pope et al. (disclosing patient position monitor with timer), U.S. Patent Application Publication No. 2010/0039269 to Newham (disclosing modular systems for monitoring the presence of a person using a variety of sensing devices), U.S. Patent Application Publication No. 2010/0225488 to Hinterlong (disclosing a patient monitoring system using an active mattress or chair system), and U.S. Patent Application Publication No. 2011/0120228 to Main et al. (disclosing a capacitive pressure sensor).

The subject matter of each of the herein-referenced published patent-related documents is fully incorporated herein by reference, for all purposes.

One issue that is of increased concern in the mattress industry is the occurrence of “bottoming out” of a patient on a mattress. When a patient bottoms out, the patient may no longer be generally supported by the mattress. Such lack of support can lead to significant safety and medical concerns. For example, patients may become injured due to contact with the surfaces on which the mattresses are positioned, due to a loss of support between the patient and the surface. Further, patients may develop decubitus ulcers (pressure sores or bedsores), which are often caused by pressure, friction, shear forces, moisture, and/or heat, due to a lack of circulation in the mattress caused by bottoming out.

Another issue of increased concern in the mattress industry is pressure distribution throughout the mattress. Many currently known mattresses fail to adequately distribute pressure throughout the mattress, thus causing pressure peaks to occur at various locations throughout the mattress and causing user discomfort and susceptibility to ulcer formation.

Accordingly, a system for adjusting the support of a mattress during use by, for example, a patient, would be desired in the art. Further, a system that can detect and prevent bottoming out would be advantageous. Still further, a system that provides improved pressure distribution and/or redistribution would be advantageous.

SUMMARY OF THE SUBJECT MATTER

Aspects and advantages of the presently disclosed subject matter will be set forth in part in the following description, or may be apparent from the description, or may be learned through practice of the presently disclosed subject matter.

In view of the recognized features encountered in the prior art and addressed by the presently disclosed subject matter, improved apparatus and methodology are presently disclosed for adjusting the support provided by a mattress during use. It is a general object of the present disclosure to provide a mattress and a capacitive immersion system for a mattress. The capacitive immersion system may advantageously adjust the mattress as desired or required to prevent a user supported on the mattress, such as a patient, from bottoming out. Additionally, the capacitive immersion system may allow maximization of the immersion of a user in the mattress, while preventing bottoming out, thus maximizing pressure distribution throughout the mattress. The capacitive immersion system may further advantageously provide the user with optimized/controlled pressure levels for the mattress.

A present exemplary mattress includes one or more air cells and a capacitive immersion system. The system relates generated capacitance between conductors mounted to an air cell to a pressure inside the air cell on which the conductors are mounted. More specifically, the measured capacitance may be related to a distance between the conductors. This distance may then be related to the pressure within the air cells.

A present exemplary system includes a top conductor and a bottom conductor, each of which is mounted to an air cell. The conductors are connected to and in communication with a controller, which includes suitable algorithms for measuring capacitance between the conductors and relating this capacitance to a distance between the conductors. The distance may then be indirectly related to the pressure inside the air cell. The controller may further be connected to and in communication with a control system for inflating and/or deflating the air cell. The air cell may be inflated or deflated as required or desired to maintain a suitable minimum distance or distance that a user finds to be subjectively comfortable.

In some embodiments, the system includes a shield. The shield blocks capacitance generated from a user of a mattress from interfering with the generated capacitance between the conductors.

Another exemplary embodiment of the presently disclosed subject matter includes an adjustable mattress for supporting a user thereon. Such a mattress preferably comprises at least one adjustable fluid chamber, a control system, a pair of conductor elements, and a feedback loop. Further such adjustable fluid chamber preferably has respective top and bottom sides thereof; the control system associated with such fluid chamber preferably controls the degree of inflation of such fluid chamber, for thereby controlling the distance between the respective top and bottom sides thereof; the pair of conductor elements preferably are respectively associated with such top and bottom fluid chamber sides, for comprising a capacitive component for generating capacitance between such conductor elements based at least in part on the distance between such conductor elements; and such feedback loop preferably is interconnecting such capacitance with such control system, with such control system configured to control the inflation of such fluid chamber so as to maintain at least a predetermined distance between such fluid chamber respective top and bottom sides. With such an exemplary arrangement, a user received on such mattress is advantageously prevented from bottoming out against the fluid chamber bottom side.

In some variations of the foregoing adjustable mattress, such at least one adjustable fluid chamber may comprise a plurality of air cells; and at least one of such pair of conductor elements may comprise a wire conductor. In others thereof, such at least one adjustable fluid chamber may comprise a plurality of air cells; and such control system may be configured to control inflating and deflating of such air cells.

Variations of the foregoing presently disclosed adjustable mattress exemplary embodiments may further include a frame formed of respective foam elements, and having a central cavity formed by such foam elements, and receiving such plurality of air cells; and a shield within such frame and situated between such air cell upper sides and a user received on such mattress for reducing interference with capacitance generated between such conductor elements.

In other presently disclosed alternatives, such shield may comprise one of metal strips and metal plate construction; and such metal may comprise at least one of aluminum, copper, nickel, and iron.

In yet other present variations, an exemplary adjustable mattress may further include a plurality of such pairs of conductor elements, with at least one top conductor and at least one associated bottom conductor mounted to each of such respective plurality of air cells, and with each top conductor and associated bottom conductor defining a capacitance therebetween; and such conductor elements may comprise one of wire, strip, and plate metal sensors.

In yet others, such control system may further include a controllable pump and associated air hoses interconnected with such air cells for controllably inflating and deflating such air cells; and such plurality of air cells may be respectively aligned with respective portions of a user's body supported thereon.

Yet other present exemplary embodiments of presently disclosed subject matter relate to a patient support mattress with capacitive immersion control for adjusting the support that the mattress provides to the patient. Such exemplary mattress may comprise a frame formed of respective foam elements, and having a generally central cavity formed by such foam elements; a plurality of air cells received in such cavity, and adapted to be controllably inflated; an inflation pump system associated with such air cells and configured for being activated for controlling the degree of inflation of such air cells; at least one pair of conductors, associated with respective upper and lower surfaces of such air cells and configured for generating capacitance based on the distance between such upper and lower surfaces; and a controller. Preferably in such exemplary arrangements, such controller is provided for receiving an input based on such generated capacitance, and configured for activating such inflation pump system so as to maintain a predetermined distance between such upper and lower surfaces, so as to immerse a patient in such mattress while preventing bottoming out of such patient against such air cell lower surfaces.

In some variations of the foregoing, such frame may comprise a casing; such foam elements may comprise foam bolsters and foam sides running the length of such mattress and on either side thereof, and a foam header and foam footer at the respective ends of such mattress and capping the foam bolsters and sides; and such mattress may further include a topper in such casing and defining a support surface for a patient received on such mattress.

In still other present variations, such controller may be calibrated based on measured capacitances with and without a patient received on such mattress to establish what is a minimum distance greater than a bottoming out distance, and may be configured to inflate and deflate such air cells so as to keep such mattress from bottoming out.

Yet other present alternatives relate to a patient support mattress wherein such inflation pump system may include an air pump and air hoses interconnecting such air pump to such air cells, so that such controller can inflate or deflate such air cells through activation of such air pump as needed for preventing a patient from bottoming out.

Others thereof may relate to a patient support mattress which may further include a plurality of such pairs of conductor elements, with at least one top conductor and at least one associated bottom conductor mounted to each of such respective plurality of air cells, with each top conductor and associated bottom conductor defining a capacitance therebetween; a shield within such frame and situated between such air cell upper surfaces and a patient received on such mattress for reducing interference with capacitance generated between such conductors; and wherein such conductor elements may comprise one of wire, strip, and plate metal sensors.

It is to be understood by those of ordinary skill in the art from the complete disclosure herewith that the presently disclosed subject matter equally relates to devices/apparatus as well as related and/or corresponding methodologies. One such presently disclosed exemplary methodology relates to a method for controlling an adjustable support to prevent bottoming out of a patient received thereon. Such method preferably comprises providing an adjustable support having at least one air cell supporting a patient and adapted to be controllably inflated and deflated; providing at least one pair of conductors, associated with respective upper and lower surfaces of the air cell and configured for generating capacitance based on the distance between such upper and lower surfaces; and controlling the degree of inflation of the air cell based on the generated capacitance to maintain a predetermined distance between the upper and lower surfaces, so as to immerse a patient in such support while preventing bottoming out of such patient against the air cell lower surface.

In variations of the foregoing, the adjustable support may comprise one of a bed, wheelchair, and specialized transport.

In other variations thereof, the adjustable support may comprise a patient support mattress having a plurality of air cells interconnected with a controllable air pump and corresponding plurality of air hoses, for controlled inflating and deflating of such air cells. In some such variations, the air cells may be grouped into respective patient support regions and respectively controlled. In some of such further variations, the grouped air cells may be respectively controlled through alternate inflation and deflation to assist turning a patient supported on the mattress, while using the generated capacitance to controllably inflate the air cells at at least minimum levels to prevent patient bottoming out.

In other presently disclosed alternatives, exemplary methodology may further include a frame formed of respective foam elements, and having a central cavity formed by such foam elements, and receiving the plurality of air cells; and a plurality of pairs of conductors, with at least one top conductor and at least one associated bottom conductor mounted to each of the respective plurality of air cells, with each top conductor and associated bottom conductor defining a capacitance therebetween; and wherein such conductors may comprise one of wire, strip, and plate metal sensors.

In other variations, methodology may further include a shield within such frame and situated between the air cell upper surfaces and a patient received on such mattress for reducing interference with capacitance generated between such conductors. In yet others, such controller may be calibrated based on measured capacitances with and without a patient received on the mattress; such controller may be configured for being calibrated to know what is a minimum distance greater than a bottoming out distance, and to inflate and deflate such air cells so as to keep the mattress from bottoming out; and such controller input may comprise one of a constant feedback loop and a signal received at determined intervals.

Additional objects and advantages of the presently disclosed subject matter are set forth in, or will be apparent to, those of ordinary skill in the art from the detailed description herein. Also, it should be further appreciated that modifications and variations to the specifically illustrated, referred and discussed features, elements, and steps hereof may be practiced in various embodiments and uses of the presently disclosed subject matter without departing from the spirit and scope of the subject matter. Variations may include, but are not limited to, substitution of equivalent means, features, or steps for those illustrated, referenced, or discussed, and the functional, operational, or positional reversal of various parts, features, steps, or the like.

Still further, it is to be understood that different embodiments, as well as different presently preferred embodiments, of the presently disclosed subject matter may include various combinations or configurations of presently disclosed features, steps, or elements, or their equivalents including combinations of features, parts, or steps or configurations thereof not expressly shown in the figures or stated in the detailed description of such figures. Additional embodiments of the presently disclosed subject matter, not necessarily expressed in the summarized section, may include and incorporate various combinations of aspects of features, components, or steps referenced in the summarized objects above, and/or other features, components, or steps as otherwise discussed in this application. Those of ordinary skill in the art will better appreciate the features and aspects of such embodiments, and others, upon review of the remainder of the specification. The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the presently disclosed subject matter and, together with the description, serve to explain the principles of the presently disclosed subject matter.

BRIEF DESCRIPTION OF THE DRAWINGS

A full and enabling disclosure of the presently disclosed subject matter, including the best mode thereof, directed to one of ordinary skill in the art, is set forth in the specification, which makes reference to the appended figures, in which:

FIG. 1 is a top view of an exemplary embodiment of a mattress in accordance with the present disclosure;

FIG. 2 is a cross-sectional view, along the lines 2-2 of FIG. 1, of an exemplary embodiment of a mattress in accordance with the present disclosure;

FIG. 3 is a cross-sectional view, along the lines 3-3 of FIG. 1, of an exemplary embodiment of a mattress in an unloaded position in accordance with the present disclosure;

FIG. 4 is a cross-sectional view of the mattress of FIG. 3 in a loaded position in accordance with the present disclosure;

FIG. 5 is a perspective view of an exemplary embodiment of a plurality of air cells with a top conductor of a capacitive immersion system mounted thereto in accordance with the present disclosure;

FIG. 6 is a perspective view of another exemplary embodiment of a plurality of air cells with a top conductor of a capacitive immersion system mounted thereto in accordance with the present disclosure;

FIG. 7 is a perspective view of an exemplary embodiment of a plurality of air cells with a top conductor and shield of a capacitive immersion system mounted thereto in accordance with the present disclosure;

FIG. 8 is a perspective view of another exemplary embodiment of a plurality of air cells with a top conductor and shield of a capacitive immersion system mounted thereto in accordance with the present disclosure; and

FIG. 9 is a perspective view of another exemplary embodiment of a plurality of air cells with a top conductor and shield of a capacitive immersion system mounted thereto in accordance with the present disclosure.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Reference is herein made in detail to exemplary embodiments of the presently disclosed subject matter, one or more examples of which are illustrated in or represented by the drawings. Each example is provided by way of explanation of the presently disclosed subject matter, not limitation of the presently disclosed subject matter. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in and to the presently disclosed subject matter without departing from the scope or spirit of the presently disclosed subject matter. For instance, features illustrated or described as part of one embodiment may be used with another embodiment to yield a still further embodiment. Thus, it is intended that the presently disclosed subject matter covers such modifications and variations as come within the scope of the disclosure and equivalents thereof.

Referring now to the drawings, FIGS. 1 through 4 illustrates an exemplary mattress 10. The mattress 10 includes at least one air cell 12. Exemplary air cells 12 are inflatable air bladders, which are for their alternate inflation/deflation connected directly to a control system 14, as will be more fully described below. Such air cells 12 may be operated in a manner so as to provide the primary support surface for a user, such as a patient. One, two, three, four, or more air cells 12 may be provided in a mattress 10 according to the present disclosure. The air cells 12 may have any suitable positioning relative to one another. For example, one or more air cells 12 may extend lengthwise through a head, neck, and shoulder (“upper”) portion 20, an intermediate portion 22, and a heel (“lower”) portion 24 of the mattress 10, as shown, thus generally providing support throughout the length of a user's body. In other embodiments, one or more air cells 12 may extend lengthwise through only one or more of the upper portion 20, intermediate portion 22, and/or lower portion 24. In still other embodiments, one or more air cells 12 may extend widthwise through any one or more of the upper portion 20, intermediate portion 22, and/or lower portion 24, or may extend in any suitable direction through any suitable portion of the mattress.

The mattress may in some embodiments further include a casing 30, which may at least partially define a cavity in which the air cells 12 are contained. For example, an exemplary casing 30 includes foam bolsters 32 and foam sides 34 running the length of the mattress 10 and on either side thereof. At the respective ends of the mattress 10 and capping the foam bolsters and sides 32 and 34 are, respectively, a foam header 36 and foam footer 38, which along with the bolsters 32 form the cavity in the mattress 10. Such cavity (not numbered) is configured for positioning of air cells 12 therein. It should be understood that the various components of the casing 30 are not limited to foam materials, but rather that any suitable materials are within the scope and spirit of the present disclosure.

A topper 40 may also be provided and included in the casing 30. The topper 40 may define a support surface 42 having various portions, such as the upper portion 20, intermediate portion 22, and lower portion 24. The topper 40 may be positioned between the air cells 12 and a user sitting or laying on the mattress 10.

It should further be understood that the term “mattress” is not intended to limit the present disclosure to mattresses for beds. Rather, the term “mattress” encompasses any suitable support apparatus for, for example, a bed, wheelchair or other specialized transport, chair, or other device on which a person may sit or lay at rest.

As shown in FIGS. 1 through 9, a mattress 10 according to the present disclosure may include a capacitive immersion system 50. The system 50 may be configured to measure and adjust the amount of support provided by the mattress 10 to a user supported on the mattress 10. Further, in exemplary embodiments, the system 50 may prevent “bottoming out” of a user, such as a patient, on the mattress. “Bottoming out” is a term of art in the mattress industry to generally reference the lowest point, relative to a frame, support, or other reference point, to which a user on a mattress can descend. Once a patient has bottomed out, no more significant supported descent of the patient may occur. Additionally, the capacitive immersion system may allow maximization of the immersion of a user in the mattress, while preventing bottoming out, thus maximizing pressure distribution throughout the mattress. Immersion is the distance that a user sinks into the mattress 10 when supported thereon. It should be understood that maximum immersion may be determined objectively relative to, for example, bottoming out, or may be determined subjectively for an individual user based on the comfort level of the user. When determined subjectively, the pressure distribution for the user throughout the mattress may be improved while a comfort level of the user on the mattress is maintained.

To measure and adjust the amount of support provided by the mattress 10, the system 50 may include conductors mounted to the mattress 10. The conductors may be configured to generate a capacitance therebetween. In exemplary embodiments, one or more respective top conductors 52 and bottom conductors 54 may be mounted to one or more of the air cells 12. For example, in some embodiments, at least one top conductor 52 and at least one associated bottom conductor 54 may be mounted to each of the air cells 12 in the mattress 10. Each top conductor 52 may be positioned on a top portion of an air cell 12 between the air cell 12 and a topper 40, support surface 42, and/or user. Each bottom conductor 54 may be positioned on a bottom portion of an air cell 12 between the air cell 12 and the ground, frame 55, and/or other suitable surface on which the mattress 10 is supported. Each top conductor 52 and associated bottom conductor 54 may define a capacitance therebetween.

Each of the top conductors 52 and bottom conductors 54 may be formed from any suitable capacitive material, such that a capacitance is generated between an associated top conductor 52 and bottom conductor 54. For example, FIG. 5 illustrates one embodiment of a top conductor 52, wherein the top conductor 52 is a wire sensor. FIG. 6 illustrates another embodiment of a top conductor 52, wherein the top conductor 52 is an aluminum foil strip extending lengthwise on an air cell 12. The associated bottom conductor 54 according to these embodiments may also be a wire sensor or aluminum foil strip, or may be another suitable conductor extending at least partially lengthwise and/or widthwise on one or more air cells 12. A top conductor 52 and/or bottom conductor 54 according to the present disclosure may be a wire, foil strip, plate, or other suitable device formed from aluminum, copper, nickel, iron, or any other suitable metal or other suitable material.

In some embodiments as shown in FIGS. 1 through 4 and 7 through 9, a system 50 may further include a shield 56. A shield according to the present disclosure may be configured to prevent any capacitance exhibited by a user supported on the mattress from interfering with the intended capacitance readings between the respective top and bottom conductors 52, 54 of the system 50. For example, in exemplary embodiments, a shield 56 may be positioned between a top conductor 52 and a topper 40, support surface 42, and/or user. Any capacitance exhibited by a user supported on the mattress 10 may be blocked or reduced by the shield 56 before reaching and interfering with the capacitance between an associated top conductor 52 and bottom conductor 54.

FIGS. 7 through 9 illustrate various embodiments of a shield 56 according to the present disclosure. In one embodiment, as shown in FIG. 7, a shield 56 may be an aluminum plate. In another embodiment as shown in FIG. 8, a shield 56 may be formed from widthwise extending strips, which may be formed from, for example, aluminum foil. In yet another embodiment as shown in FIG. 9, a shield 56 may be formed from lengthwise extending strips, which may be formed from, for example, copper foil. A shield 56 according to the present disclosure may be a foil strip, plate, or other suitable device formed from aluminum, copper, nickel, iron, or any other suitable metal or other suitable material.

As discussed above, a capacitance may be generated between a top conductor 52 and bottom conductor 54. This capacitance may be utilized to measure and adjust the amount of support provided by the mattress 10 to a user supported on the mattress 10. The system 50 may include a controller 60, as shown. The controller 60 may be connected to and in communication with an associated top and bottom conductor 52, 54 through, for example, wiring or other suitable apparatus. The controller 60 may thus receive an input, which may be on a constant feedback loop or which may be provided at suitable intervals, of the generated capacitance between the associated top and bottom conductor 52, 54. The controller 60 may further include suitable algorithms for relating the generated capacitance to a pressure inside one or more air cells 12 on which the conductors 52, 54 are mounted. More specifically, the measured capacitance may be related to a distance between the associated top conductor 52 and bottom conductor 54. This distance may then be related to pressure within the air cells 12.

For example, FIGS. 2 and 3 illustrate a first distance 70 between a top conductor 52 and bottom conductor 54. The first distance 70 may be a distance between the conductors 52 and 54 in, for example, an unloaded position with no user being supported on the mattress 10. FIG. 4 illustrates a second distance 72 between a top conductor 52 and bottom conductor 54. The second distance 72 may be a distance between the conductors 52 and 54 in, for example, a loaded position with a user being supported on the mattress 10. Suitable algorithms included in the controller 60 may correlate such distances 70, 72 to the capacitance generated between the top conductor 52 and bottom conductor 54 when at those respective distances 70, 72. Further, a minimum distance may be determined for a mattress 10. The minimum distance may be approximately zero or a minimum distance such that there is generally no air support at a location in an air cell 12 between a top conductor and bottom conductor, may be a designated bottoming out distance, may be a maximum immersion distance, and/or may be the second distance 72 as shown or any other suitable minimum distance. The minimum distance is thus a predetermined distance that provides a limit to how far a user supported on a mattress 10 may be allowed to sink, and thus be immersed, as discussed below. In exemplary embodiments, the minimum distance may be greater than a bottoming out distance, such that a user supported on a mattress 10 is not allowed to sink past the bottoming out distance. In further exemplary embodiments, the minimum distance may be a maximum immersion distance. In still further exemplary embodiments, the minimum distance may be a user-determined and/or user-adjustable distance.

By defining a minimum distance which in some embodiments is greater than a bottoming out distance, the present system 50, mattress 10, and methods as disclosed herein advantageously provide novel systems and methods for warning a user about, and preventing the user from, bottoming out. Previously known systems utilize alarms that are activated when a minimum pressure is reached in the mattress 10 such that bottoming out cannot be prevented. These systems are inaccurate, and in many cases fail to actually prevent bottoming out. The present system 50, by instead utilizing a minimum distance as discussed above to, for example, trigger an alarm, provides more accurate monitoring and preventing of bottoming out.

As discussed, the controller 60 may include suitable algorithms for relating a generated capacitance between a top conductor 52 and bottom conductor 54 to a distance between the top conductor 52 and bottom conductor 54. Thus, a first distance 70, second distance 72, minimum distance, and/or any other suitable distance may be determined by a measurement of capacitance. The controller 60 may further include suitable algorithms for setting the predetermined minimum distance and/or any other suitable minimum distance before or during use of the mattress. The predetermined distance may be determined to prevent bottoming out, may be determined to maximize immersion, may be determined based on the subjective comfort of a user, and/or may be determined based on any other suitable technique. Further, the controller 60 may be connected to and in communication with the control system 14 for inflating and deflating the air cells 12, and may include suitable algorithms for activating the control system 14 to inflate or deflate one or more air cells 12 as desired or required. For example, in exemplary embodiments, the controller 60 activates the control system 14 when the distance between a top conductor 52 and bottom conductor 54, as determined by capacitance as discussed above, reaches a minimum distance. The air cells 12 may be inflated or deflated as desired or required to maintain a distance that is generally greater than or equal to the minimum distance. This ensures that the distance between the conductors 52, 54 is never less than the minimum distance and, in exemplary embodiments, never reaches a bottoming out distance. The controller 60 thus indirectly relates generated capacitance to the pressure inside one or more air cells 12 on which conductors 52, 54 are mounted.

The controller 60 and control system 14 may each be included in and/or include suitable hardware, such as handheld remotes, personal digital assistants, cellular telephones, pendant controllers, or computers. Further, in some embodiments, the controller 60 and control system 14 may both be included in a single piece of hardware. The control system 14 may further include suitable apparatus for inflating and/or deflating the air cells 12. For example, the control system 14 may include a pump 82 and suitable hoses 84 connecting the pump 82 to one or more air cells 12. A manifold 86 may be included and disposed between the pump 82 and hoses 84 to direct flows therebetween, or the hoses 84 may be directly connected to the pump 82. The controller 60 may activate the control system 14, and thereby the pump 82, as desired or required to inflate or deflate the air cells 12.

The system 50 thus allows for capacitance readings to be calibrated to particular air cell 12 and/or mattress 10 embodiments, and allows for automatic adjustment of the pressure in the air cells 12 of the mattress 10 so as to prevent a supported user from bottoming out, to allow maximization of the immersion of a user in the mattress so as to maximize pressure distribution and/or redistribution throughout the mattress, and/or to otherwise provide the user with optimized/controlled pressure levels. Such control technique can be applied at an integral level to an entire mattress 10 and/or air cells 12 thereof, or to sectionalized support associated with such mattress 10, such as to air cells 12 supporting one or more of an upper portion 20, intermediate portion 22, and/or portion 24, or any sub-portions thereof.

For example, in some embodiments, the system 50 and control technique of the present disclosure may be applied to individual air cells 12 or groups of air cells 12. Such application may be particularly advantageous when a user is being turned on a mattress 12. For example, a user may independently turn on mattress, for comfort and/or medical purposes. Such turning may allow the user to alternate between lying on the back, stomach, or side. Additionally or alternatively, a user may be assisted in turning, for comfort and/or medical purposes. Such assisted turning may be performed manually, automatically, or through a hybrid manual-automatic process. A user may be manually turned by, for example, hospital staff. During a manual turn assist, a user may be moved into a specified position, and positioning aids (not shown) may be utilized to retain the user in this position. For example, a user may be rolled onto one side, and positioning aids utilized to retain the user in this position. The user may be physically moved by, for example, hospital staff, and/or various air cells 12 may be inflated and deflated to assist in moving the user. A user may be automatically turned by, for example, operation of the control system 14 using a turning algorithm. During such automatic turning, various air cells 12 may inflate and deflate according to a predetermined schedule to move the user into a specified position. In a hybrid manual-automatic process, various manual and automatic aspects as discussed herein may be combined to turn the user. Turning of the user may reduce or prevent the risk of the user developing decubitus ulcers. However, during the turning process, the various air cells 12 may be subjected to increased or decreased pressure due to the shifting mass of the user. For example, rolling of the user to one side may increase the pressure in the air cells 12 onto which the user is rolled, and decrease the pressure in the air cells 12 off of which the user is rolled. Thus, bottoming out of the air cells 12, and in particular the air cells 12 subjected to increased pressure due to the turning process, is of increased concern during the turning process.

Thus, the system 50 and control technique of the present disclosure can be applied during the turning process to prevent the user from bottoming out during turning. For example, as discussed above, respective top conductors 52 and bottom conductors 54 may be mounted to individual air cells 12. During the turning process, controller 60 may thus receive an input, as discussed above, for one or more individual air cells 12. The control system 14 may be activated as required and as discussed above to prevent bottoming out of each individual air cell 12. Thus, during, for example, rolling of a user to one side, the air cells 12 onto which the user is rolled may be inflated as required to prevent bottoming out on these air cells 12 due to operation of the system 50 and control technique as discussed herein.

In one exemplary turning process, the mattress 10 may include, for example, four lengthwise extending air cells 12. The user may be rolled to one side onto, for example, one, two or three of the air cells 12. Broken lines in FIG. 2, for example, illustrates two individual air cells 90 and 92 after a user has been turned onto the user's side on the air cells 90, 92. During rolling and while the user remains on one side, the system 50 and control technique as discussed herein may prevent the individual air cells 12 on which the user is disposed, such as air cell 90 and/or air cell 92 as shown, from bottoming out, by inflating the individual air cells 12, such as air cell 90 and/or air cell 92, as required. The user may then be rolled to another side onto, for example, one, two or three of the air cells 12, each of which may be the same or different from the previously discussed air cells 12. During this rolling and while the user remains on one side, the system 50 and control technique as discussed herein may similarly prevent the individual air cells 12 on which the user is disposed from bottoming out. The user may then be returned to an original position on the mattress 10 wherein the user may be supported by all or a portion of the lengthwise extending air cells 12, which may for example include air cells 90 and 92 as well as other air cells 12. After being returned to the original position, as well as when in the original position before rolling, the system 50 and control technique as discussed herein may similarly prevent the individual air cells 12 on which the user is disposed, including air cells 90 and 92, from bottoming out.

The present written description uses examples to disclose the presently disclosed subject matter, including the best mode, and also to enable any person skilled in the art to practice the presently disclosed subject matter, including making and using any devices or systems and performing any incorporated and/or associated methods. While the presently disclosed subject matter has been described in detail with respect to specific embodiments thereof, it will be appreciated that those skilled in the art, upon attaining an understanding of the foregoing may readily produce alterations to, variations of, and equivalents to such embodiments. Accordingly, the scope of the present disclosure is by way of example rather than by way of limitation, and the subject disclosure does not preclude inclusion of such modifications, variations and/or additions to the presently disclosed subject matter as would be readily apparent to one of ordinary skill in the art. 

What is claimed is:
 1. An adjustable mattress for supporting a user thereon, comprising: at least one adjustable fluid chamber, said fluid chamber having respective top and bottom sides thereof; a control system associated with said fluid chamber for controlling the degree of inflation of said fluid chamber, for thereby controlling the distance between the respective top and bottom sides thereof; a pair of conductor elements respectively associated with said top and bottom fluid chamber sides, for comprising a capacitive component for generating capacitance between said conductor elements based at least in part on the distance between such conductor elements; and a feedback loop interconnecting said capacitance with said control system, with said control system configured to control the inflation of said fluid chamber so as to maintain at least a predetermined distance between said fluid chamber respective top and bottom sides, so that a user received on said mattress is prevented from bottoming out against the fluid chamber bottom side.
 2. An adjustable mattress as in claim 1, wherein: said at least one adjustable fluid chamber comprises a plurality of air cells; and at least one of said pair of conductor elements comprises a wire conductor.
 3. An adjustable mattress as in claim 1, wherein: said at least one adjustable fluid chamber comprises a plurality of air cells; and said control system is configured to control inflating and deflating of said air cells.
 4. An adjustable mattress as in claim 3, further including: a frame formed of respective foam elements, and having a central cavity formed by said foam elements, and receiving said plurality of air cells; and a shield within said frame and situated between said air cell upper sides and a user received on said mattress for reducing interference with capacitance generated between said conductor elements.
 5. An adjustable mattress as in claim 4, wherein: said shield comprises one of metal strips and metal plate construction; and said metal comprises at least one of aluminum, copper, nickel, and iron.
 6. An adjustable mattress as in claim 3, further including: a plurality of said pairs of conductor elements, with at least one top conductor and at least one associated bottom conductor mounted to each of said respective plurality of air cells, and with each top conductor and associated bottom conductor defining a capacitance therebetween; and wherein said conductor elements comprise one of wire, strip, and plate metal sensors.
 7. An adjustable mattress as in claim 3, wherein: said control system further includes a controllable pump and associated air hoses interconnected with said air cells for controllably inflating and deflating said air cells; and said plurality of air cells are respectively aligned with respective portions of a user's body supported thereon.
 8. A patient support mattress with capacitive immersion control for adjusting the support that the mattress provides to the patient, comprising: a frame formed of respective foam elements, and having a generally central cavity formed by said foam elements; a plurality of air cells received in said cavity, and adapted to be controllably inflated; an inflation pump system associated with said air cells and configured for being activated for controlling the degree of inflation of said air cells; at least one pair of conductors, associated with respective upper and lower surfaces of said air cells and configured for generating capacitance based on the distance between such upper and lower surfaces; and a controller for receiving an input based on such generated capacitance, and configured for activating said inflation pump system so as to maintain a predetermined distance between said upper and lower surfaces, so as to immerse a patient in said mattress while preventing bottoming out of such patient against said air cell lower surfaces.
 9. A patient support mattress as in claim 8, wherein: said frame comprises a casing; said foam elements comprise foam bolsters and foam sides running the length of said mattress and on either side thereof, and a foam header and foam footer at the respective ends of said mattress and capping the foam bolsters and sides; said mattress further includes a topper in said casing and defining a support surface for a patient received on said mattress.
 10. A patient support mattress as in claim 8, wherein said controller is calibrated based on measured capacitances with and without a patient received on said mattress to establish what is a minimum distance greater than a bottoming out distance, and is configured to inflate and deflate said air cells so as to keep said mattress from bottoming out.
 11. A patient support mattress as in claim 8, wherein said inflation pump system includes an air pump and air hoses interconnecting said air pump to said air cells, so that said controller can inflate or deflate said air cells through activation of said air pump as needed for preventing a patient from bottoming out.
 12. A patient support mattress as in claim 8, further including: a plurality of said pairs of conductor elements, with at least one top conductor and at least one associated bottom conductor mounted to each of said respective plurality of air cells, with each top conductor and associated bottom conductor defining a capacitance therebetween; a shield within said frame and situated between said air cell upper surfaces and a patient received on said mattress for reducing interference with capacitance generated between said conductors; and wherein said conductor elements comprise one of wire, strip, and plate metal sensors.
 13. A method for controlling an adjustable support to prevent bottoming out of a patient received thereon, comprising: providing an adjustable support having at least one air cell supporting a patient and adapted to be controllably inflated and deflated; providing at least one pair of conductors, associated with respective upper and lower surfaces of the air cell and configured for generating capacitance based on the distance between such upper and lower surfaces; and controlling the degree of inflation of the air cell based on the generated capacitance to maintain a predetermined distance between the upper and lower surfaces, so as to immerse a patient in such support while preventing bottoming out of such patient against the air cell lower surface.
 14. A method as in claim 13, wherein the adjustable support comprises one of a bed, wheelchair, and specialized transport.
 15. A method as in claim 13, wherein the adjustable support comprises a patient support mattress having a plurality of air cells interconnected with a controllable air pump and corresponding plurality of air hoses, for controlled inflating and deflating of such air cells.
 16. A method as in claim 15, wherein the air cells are grouped into respective patient support regions and respectively controlled.
 17. A method as in claim 16, wherein the grouped air cells are respectively controlled through alternate inflation and deflation to assist turning a patient supported on the mattress, while using the generated capacitance to controllably inflate the air cells at at least minimum levels to prevent patient bottoming out.
 18. A method as in claim 15, further including: a frame formed of respective foam elements, and having a central cavity formed by such foam elements, and receiving the plurality of air cells; and a plurality of pairs of conductors, with at least one top conductor and at least one associated bottom conductor mounted to each of the respective plurality of air cells, with each top conductor and associated bottom conductor defining a capacitance therebetween; and wherein such conductors comprise one of wire, strip, and plate metal sensors.
 19. A method as in claim 18, further including a shield within such frame and situated between the air cell upper surfaces and a patient received on such mattress for reducing interference with capacitance generated between such conductors.
 20. A method as in claim 18, wherein: such controller is calibrated based on measured capacitances with and without a patient received on the mattress; such controller is configured for being calibrated to know what is a minimum distance greater than a bottoming out distance, and to inflate and deflate such air cells so as to keep the mattress from bottoming out; and such controller input comprises one of a constant feedback loop and a signal received at determined intervals. 